Portable electronic device with an animated graphical user interface



FIG. 1 is the first image in a sequence for a portable electronic device with an animated graphical user interface showing our new design;

FIG. 2 is the second image thereof; and,

FIG. 3 is the third image thereof.

The appearance of the transitional image sequentially transitions between the images shown in FIGS. 1-3. The process or period in which one image transitions to another forms no part of the claimed design. The broken line showing of the remainder of the animated graphical user interface and of a portable electronic device forms no part of the claimed design. 

CLAIM The ornamental design for a portable electronic device with an animated graphical user interface, as shown and described. 